JP3452489B2 - Image splicing method and apparatus, and storage medium storing program - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention synthesizes overlapping portions of first and second binary images with digital first and second binary images having adjacent arrangement relations and having overlapping portions. hand,
The present invention relates to an image joining processing method for joining a first binary image and a second binary image, an apparatus therefor, and a storage medium recording a program.

[0002]

2. Description of the Related Art When a large-sized original is read by a scanner or the like to obtain a digital binary image (black and white image),
In order to obtain a binary image NG with a higher resolution, for example, as shown in FIG. 15, the reading of the original OG by the scanner is performed in a divided manner, and each binary image NG obtained by the division is read.
A method of joining A and NGB by post-treatment is adopted.

FIG. 15 shows a case where the original OG is divided and read in the X direction. The first binary image NGA is
The second binary image NGB is a binary image obtained by reading the image in the first reading area OGA in the original OG, and the second binary image NGB is a binary image obtained by reading the image in the second reading area OGB in the original OG. Is.

Further, the first and second read areas OGA,
The first and second binary images NG by overlapping a part of OGB
Include the same image part OW of the original OG in A and NGB,
The first binary image NGA is created by synthesizing the overlapping portion WA (pixel range of width WW in the X direction) in each binary image NGA, NGB.
And the second binary image NGB are connected to each other.

Conventionally, the overlapping of the first and second binary images NGA and NGB in the above-described method has been performed.
This is performed by a method of setting a joint position at A and using the joint position as a boundary to simply combine the first and second binary images NGA and NGB.

[0006]

PROBLEM TO BE SOLVED BY THE INVENTION First binary image NGA
If the image of the overlapping portion WA of the first binary image NGA and the image of the overlapping portion WA of the second binary image NGB match, there is no problem even if the first and second binary images NGA and NGB are connected by the conventional method. Absent.

However, the first and second binary images NG
The image of the overlapping portion WA of the first binary image NGA and the second binary image due to mechanical precision error of an input device such as a scanner for reading A, NGB, or distortion of an optical system in the input device for reading the image. The image of the overlapping portion WA of the image NGB often deviates.

Thus, the first and second binary images NGA,
When the images of the overlapping portion WA of NGB are misaligned, if the first and second binary images NGA and NGB are joined by the conventional method, the binary image NG after joining has an image shift at the joining position. The inconvenience of being conspicuous occurs.

For example, as shown in FIG. 16, the connecting position K
L is always set to the same position and the first and second binary images NG
If A and NGB are simply combined, the first and second binary images N
Even if there is a slight shift in the image of the overlapping portion WA of GA and NGB, the shift of the image that occurs in the binary image NG after joining is visually noticeable, and especially, the first and second binary images. When the image of the overlapping portion WA of NGA and NGB is a halftone dot image, a shift may appear significantly.

Therefore, as shown in FIG. 17, the joint position KL is randomly set for each of the pixel columns GLA and GLB in the joint direction, and the first and second binary images NGA and NGB are simply combined, that is, so-called random. By joining the first and second binary images NGA and NGB in the joining process,
The case where the image of the overlapping portion WA of the first and second binary images NGA and NGB is a halftone image, or the first and second binary images N
When the images in the overlapping portion WA of GA and NGB are slightly misaligned, the images can be joined together with relatively high accuracy. The pixel rows GLA and GLB in the connecting direction
Is a column of pixels lined up in the arrangement direction of the first and second binary images NGA and NGB.

However, for example, when the first and second binary images NGA and NGB shown in FIG. 18 have large deviations in the overlapped image WA of the first and second binary images NGA and NGB. For example, when the images are joined by the random joining process, there is an inconvenience that, as shown in FIG. 19, the image shift occurring in the binary image (ΔGN) after the joining is rather conspicuous. Further, if the joint position KL is always set to the same position for the first and second binary images NGA and NGB shown in FIG.
As shown in 0, the binary image (ΔGN) after stitching
The image shift that occurs in 1) will be more noticeable. In addition,
In FIGS. 19 and 20, the first and second binary images NGA, N
It shows a case where a part of the images ΔGA and ΔGB of the overlapping portion WA of GB are combined. In addition, the shaded portions in FIGS. 18 to 20 are black portions of the binary image (the portions where the density data is “1”), and the blank portions are the white portions of the binary image (the portions where the density data is “0”). ).

The present invention has been made in view of such circumstances, and an image can be accurately joined even if there is an image shift in the overlapping portion of the first and second binary images. An object of the present invention is to provide a connection processing method, its apparatus, and a storage medium storing a program.

[0013]

In order to achieve the above object, the inventors of the present invention have made the first and second binary images NGA, NG.
We have developed a blending joint process that can join images with high accuracy even if the images in the overlapping portion WA of B are greatly misaligned.

This familiarizing and connecting process comprises first to fourth steps as described in the claims.

This familiarizing process will be described with reference to the functional block diagram of FIG. 1 and the process conceptual diagrams of FIG. 2 and FIG.

First, the synthesizing means 13a is composed of the first and second two.
A pixel row GLAi in the connecting direction (X direction in the figure) of the first binary image NGA belonging to the combined area SA (pixel range of width SW in X direction) including at least a part of the overlapping portion WA of the value images NGA and NGB. Each pixel G (jA, i) (jA = XA, (XA + 1), in (i = 1, 2, ..., Y _MAX )
, (XA + (SW-1)), where XA is the composite area S
Density data (determined by A) (2 of "0" and "1")
Value density data), the first mixture ratio MRA in which the weight of the pixel on the second binary image NGB side becomes smaller is set to each pixel G.
The result RTA obtained by multiplying by (jA, i)
i and the pixel row GL in the joining direction of the first binary image NGA
Each pixel G (j belonging to the combining area SA in the pixel row GLBi in the connecting direction of the second binary image NGB corresponding to Ai
B, i) (jB = XB, (XB + 1), ..., (XB +
(SW-1)), where XB is determined by the composite area SA), but with respect to the density data (binary density data of “0” and “1”) of the pixel on the first binary image NGA side. The second mixture ratio MRB, which reduces the load, is set to each pixel G (jB, i).
For each pixel G (jA, i) and G (jB, i) corresponding to the result RTBi obtained by multiplying each pixel, and synthesizing and combining the respective pixels GLAi, GL in the connecting direction.
The first step is performed for each Bi.

By this first step, the density data of each pixel G1 (k, i) (k = 1, 2, ..., SW) in each pixel row GLM1i in the connecting direction belonging to the combined area SA after combining is obtained. It can be multi-valued.

The composite area SA may be an area including at least a part of the overlapping part WA, and a part of the overlapping part WA may be the combining area SA, or the entire overlapping part WA may be the combining area SA. Good.

Further, the first and second mixing ratios MRA, MRB
May gradually change the mixing ratio as shown in FIGS. 4 (a) and 4 (b), or may change the mixing ratio stepwise to some extent as shown in FIGS. 4 (c) and 4 (d). You may let me. However, the first and second mixture ratios MRA and MRB are set so that the total of the corresponding pixels becomes “1.0”.

Returning to FIG. 1 and FIG. 2, next, the smoothing processing means 13b includes each pixel row GLM1i in the connecting direction belonging to the combination area SA combined by the combining means 13a (first step).
The second step is performed by performing the smoothing process on the density data of each pixel G1 (k, i) in the inside. This smoothing processing is, for example, a well-known filter that performs weighted averaging of several pixels around each target pixel G1 (k, i) with each pixel G1 (k, i) in each pixel column GLM1i as a target pixel in sequence. Do by processing.
By this second step, the density data of each pixel G2 (k, i) in each pixel row GLM2i in the connecting direction belonging to the synthesis area SA reflects the density data of the peripheral pixels and becomes a multilevel gradation. Can be increased.

The smoothing process in the second step is shown in FIG.
As shown in (a), the weighted average of the pixel of interest G1 (k, i) and the pixels on the left and right of the pixel of interest G1 (k, i) is used by using only the pixels in the pixel row GLM1i in the connecting direction. Alternatively, as shown in FIG. 5B, the pixel row GL in the connecting direction including the target pixel G1 (k, i).
Weighted averaging of the pixel of interest G1 (k, i) and its surrounding pixels (pixels in the processing area FA) is performed using the pixels in M1i and the pixels in the pixel columns before and after the pixel column GLM1i. May be. Further, using the pixels in the pixel rows before and after the pixel row GLM1i in the connecting direction including the pixel of interest G1 (k, i), the pixel of interest G1 (k, i) and the pixels above and below it (FIG. 5B). G1 (k, i-1), G1 (k, i +)
Weighted averaging with 1)) may be performed.

As the weight, the same weight may be set for all the pixels to be processed, or the weight of the target pixel may be set to be the largest and the weight may be set to be smaller as the distance from the target pixel increases.

Further, in FIG. 5A, m = 3, but m = 5, 7, ... May be used. Also in FIG. 5B, m
Xn = 3 × 3, but m × n = 5 × 5, 7 × 7,
May be ... Even when the weighted average of the pixel of interest G1 (k, i) and the pixels above and below it is performed, n is not limited to 3 and n
= 5, 7, ...

Further, in FIG. 5A, G1 (1,
When i) is the target pixel, the target pixel G1 (1,
i) and several pixels on the right side thereof may be used to perform weighted averaging, and the pixel on the left side of the target pixel G1 (1, i) may be the first pixel.
Weighted averaging may be performed by supplementing from the binary image NGA. In FIG. 5A, when G1 (SW, i) is the target pixel, similarly, the weighted average may be performed using the target pixel G1 (SW, i) and several pixels on the left side thereof,
The pixel on the right side of the target pixel G1 (SW, i) is set to the second pixel
Weighted averaging may be performed by supplementing from the value image NGB. In FIG. 5B, also when the peripheral pixel in the synthesis area SA is set as the target pixel, similarly, weight averaging is performed using a part of the pixels in the processing area for weight averaging, or right and left of the target pixel. Regarding the pixels, the first and second binary images NGA, N
It suffices to replenish necessary pixels from GB and perform weighted averaging. When performing weighted averaging of the pixel of interest G1 (k, i) and the pixels above and below it, G1 (k, 1) and G1
Even when (k, Y _MAX ) is the target pixel, the weighted average may be performed using some pixels in the processing area for weighted average.

Returning to FIG. 1 and FIG. 2, next, the threshold value processing means 13c belongs to the joint area SA which has been subjected to the smoothing processing by the smoothing processing means 13b (second step), in the joint direction. Threshold processing (f {G2 (k, i), S) is performed on the density data of each pixel G2 (k, i) in the pixel column GLM2i.
L}) is performed to perform binarization, and the third step is performed. This threshold processing (f {G2 (k, i), SL}) is performed with G3 (k, i) (concentration data)> SL when G2 (k, i) (concentration data)> SL with a predetermined threshold SL as a boundary. ) (Concentration data of) is “1”, and when G2 (k, i) (concentration data of) ≦ SL, G3 (k, i) (concentration data) is set to “0”,
This is a process of converting the density data of each pixel G2 (k, i) in each pixel row GL2i in the joining direction belonging to the multivalued synthesis area SA into a binary value of “0” and “1”. This third
By the process of, the multi-valued density data of each pixel G2 (k, i) in each pixel row GL2i in the connecting direction belonging to the composite area SA is returned to binary (“0”, “1”), Each pixel row GL3i in the connecting direction that belongs to the synthesis area SA is obtained.

Then, the image joining means 13d is
The first binary image NGA and the second binary image NGB including the result RTX binarized by the threshold value processing means 13c (third step) are joined together, and the image N after joining is joined.
Get G.

The familiarizing and connecting process can be realized by the following procedure, for example.

(1) After performing the first step for all pixel columns in the connecting direction, the second to fourth steps are sequentially performed for the entire synthesis area SA.

(2) The smoothing process of the second step is shown in FIG.
As shown in (a), when processing is performed using only the pixels in the pixel row in the connecting direction that includes the target pixel,
The fourth step is sequentially repeated for each pixel column i = 1 to Y _MAX in the connecting direction.

(3) The smoothing process of the second step is shown in FIG.
As shown in (a), when processing is performed using only the pixels in the pixel row in the connecting direction that includes the target pixel,
The third step is sequentially repeated for each pixel column i = 1 to Y _MAX in the connecting direction, and the fourth step is performed using the processing result RTX.

For example, when the first and second binary images NGA and NGB (ΔGA, ΔGB) shown in FIG. 18 are joined by the fitting and joining process, the result is as follows.

Here, in order to simplify the description, a case will be described in which processing is performed for each pixel column in the connecting direction.

FIG. 6 shows corresponding one pixel columns GLAi, GL from the first and second binary images NGA, NGB shown in FIG.
The result of performing the first step on Bi is shown.

FIG. 7 shows the result of sequentially performing the second to fourth steps with respect to the result of the first step shown in FIG. In addition,
Here, in the smoothing process of the second step, using only the pixels in the pixel row in the connecting direction that includes the target pixel, a total of 3 pixels, that is, the target pixel and each of the left and right 1 pixels of the target pixel, The weight of the pixel on the left side of: the weight of the pixel of interest: the weight of the pixel on the right side of the pixel of interest = 1: 1: 1 is averaged.
Further, in the threshold value processing of the third step, the threshold value SL is set to "0.5".

The first and second binary images NG shown in FIG.
In the partial images ΔGA and ΔGB of A and NGB, all pixel columns GLAi and GLBi in the connecting direction are the same,
The processing results are all the same. Therefore, ΔG shown in FIG.
When A and ΔGB are joined together by the fitting process, ΔGN shown in FIG. 8 is obtained.

As is clear from the above-mentioned processing result, according to the blending and joining processing, in the first step, the first and second binary images are first assigned to each pixel row in the corresponding joining direction. , The results of applying the second mixture ratios are added and combined, and the binary image is multivalued, and then smoothing processing is performed in the second step to reflect the density data of the peripheral pixels. To increase the gradation of multi-value conversion, then in the third step, threshold processing is performed to return to a binary image, and in the fourth step, the result of the binarization is included in the first image. Since the processing is performed so that the value image and the second binary image are joined together, even if the first and second binary images are misaligned, the images after joining are not noticeably misaligned. , It is possible to perform smooth image joining, and to achieve accurate image joining. .

Further, as shown in FIG. 9A, among the pixels in the pixel row in the joining direction of the first binary image NGA belonging to the composite area SA, the pixel is closer to the second binary image NGB side. The more pixels, the greater the distortion of the optical system of the input device 2 (the optical system in the scanner head 100a) that captures the first binary image NGA. Similarly, as shown in FIG. 9B, among the pixels in the pixel row in the joining direction of the second binary image NGB belonging to the combination area SA, the pixel closer to the first binary image NGA side , An input device 2 for capturing the second binary image NGB
The distortion of the optical system (the optical system in the scanner head 100b) becomes large.

Therefore, the first mixture ratio MRA to be applied to the density data of each pixel in the pixel row of the first binary image NGA belonging to the composite area SA in the connecting direction is set to the value on the side of the second binary image NGB. The second mixture ratio MRB, which is set so that the pixel weight is small, and which acts on the density data of each pixel in the pixel row of the second binary image NGB belonging to the combination area SA in the joining direction, is set to By setting the weight of the pixel on the binary image NGA side to be small and combining the two, the distortion of the optical system of the input device 2 is reduced, and the first binary image NGA belonging to the combination area SA is connected. The density data of each pixel in the pixel row in the horizontal direction and the density data of each pixel in the pixel row in the connecting direction of the second binary image NGB belonging to the combining area SA can be combined to combine the images. Can improve accuracy .

In addition to the first and second binary images NGA and NGB shown in FIG. 18, the inventors of the present invention have made the first and second binary images NGA and NGB familiar with each other. When a simulation was carried out in which the pieces were joined together by the joining treatment, approximately good results were obtained.

However, the first and second binary images NG
The image of the overlapping portion WA of A and NGB is a halftone image,
It has been found that when the images are misaligned in the overlapping portion WA of the first and second binary images NGA and NGB, halftone dots disappear in the image NG after the joining process.

This is due to the synthesizing process of the first step and the second step.
It is considered that blurring occurs in the halftone dot portion due to the smoothing process in the step of (2) and the blurring is returned to the binary value, so that the halftone dot of the image NG after the joining disappears.

That is, the first and second binary images NGA,
As in the case where the image of the overlapping portion WA of NGB is a halftone image and the image is displaced in the overlapping portion WA of the first and second binary images NGA and NGB, the first and second binary images Image N
In the overlapping portion WA of GA and NGB, the number of pixels (deviation pixel number) in which the density data of the pixel on the first binary image NGA side and the density data of the pixel on the second binary image NGB side differ are compared. It has been found that, when the number is too small, good image joining cannot be performed in some cases by the licking and joining process.

Also, the first and second binary images NGA, NG
The contents of the image in the overlapping portion WA of B, the degree of deviation, and the like are not necessarily the same for the first and second binary images NGA and NGB as a whole. That is, the first and second binary images N
Some of GA and NGB can be satisfactorily joined together by the licking and joining process described above, but in other portions, the joining accuracy may be reduced when they are joined by the above licking and joining process. There is a case to consider.

Based on the above research, the present inventors have made the following invention capable of accurately connecting various first and second binary images.

That is, according to the first aspect of the present invention, the first and second digital signals having an arrangement relationship adjacent to each other having an overlapping portion are provided.
An image stitching processing method for stitching the first binary image and the second binary image by synthesizing the overlapping portions of the first and second binary images with respect to the binary image of The weight of the pixel on the side of the second binary image becomes smaller than the density data of each pixel in the pixel row in the joining direction of the first binary image belonging to the composite area including at least a part of the overlapping portion. The result of applying the first mixing ratio and the pixels belonging to the composite area in the pixel row in the joining direction of the second binary image corresponding to the pixel row in the joining direction of the first binary image A process of adding the density data and the result of applying the second mixture ratio, which reduces the weight of the pixel on the first binary image side, to each corresponding pixel to synthesize the density data, The first step performed for each column and the connection that belongs to the composite area synthesized in the first step A second step of performing smoothing processing on density data of each pixel in each pixel column direction, the second
The third step of performing thresholding on the density data of each pixel in each pixel row in the connecting direction belonging to the composite area, which has been subjected to the smoothing processing in step 3, and binarizing the density data; The process including the fourth step of joining the first binary image and the second binary image including the result of binarizing in the step of step 4 is set as the joining step and is set in the overlapping portion. A joint position is randomly set for each pixel column in the joint direction, and a process of simply combining the first binary image and the second binary image with the joint position as a boundary is a random joint process. Density data of each pixel belonging to the overlapping portion in at least one pixel row in the connecting direction of the first binary image, and second density data corresponding to each pixel row in the connecting direction of the first binary image. At least 1 in the connecting direction of the value images
By comparing the density data of each pixel belonging to the overlapping portion in one pixel row, the density data of the pixel on the first binary image side and the density data of the pixel on the second binary image side are different. The number of pixels (deviation pixel number) is checked, and if the deviation pixel number exceeds a predetermined determination pixel number, each pixel row in the joining direction is subjected to the first and second fitting processes. Two
The value images are stitched together. On the other hand, if the number of shifted pixels is not more than the judgment pixel number, the first and second binary images are stitched together by the random stitching process for each pixel row in the stitching direction. The processing is performed on all pixel columns in the joining direction to join the entire first and second binary images.

According to the second aspect of the present invention, the overlapping portions of the first and second binary images are combined with the digital first and second binary images having the adjacent arrangement relationship and having the overlapping portions. And an image stitching processing device that stitches the first binary image and the second binary image together, the stitching direction of the first binary image belonging to the synthesis area including at least a part of the overlapping portion. Second density data for each pixel in the pixel row of
And the result of applying the first mixing ratio in which the pixel load on the binary image side becomes smaller, and the second mixing direction of the second binary image corresponding to the pixel row of the first binary image in the connecting direction. The result of applying a second mixture ratio, which reduces the weight of the pixel on the first binary image side, is added to the density data of each pixel belonging to the composite area in the pixel row, for each corresponding pixel. And a smoothing process for the density data of each pixel in each pixel row in the joining direction belonging to the above-mentioned synthesis area that is synthesized by the synthesizing means. And a threshold value process is performed on the density data of each pixel in each pixel row in the joint direction belonging to the composite area that has been subjected to the smoothing process by the smoothing process unit. And a threshold processing means for converting the threshold value to 2 The jointing processing means including an image joining means for joining the first binary image and the second binary image including the digitized result, and the joining position set in the overlapping portion, in the joining direction. Of the first binary image and a random connection processing unit that simply sets the first binary image and the second binary image with the connection position as a boundary. Density data of each pixel belonging to the overlapping portion in at least one pixel row in the joining direction and at least a second binarizing image in the joining direction corresponding to each pixel row in the joining direction of the first binary image. The density data of the pixels on the first binary image side and the density data of the pixels on the second binary image side are different by comparing the density data of the pixels belonging to the overlapping portion in one pixel row. The number of pixels (shift pixel number) If the number of shifted pixels exceeds the predetermined number of determination pixels, the first and second binary images are joined by the joining processing means that blends each pixel row in the joining direction. If the number of shifted pixels is less than or equal to the determination pixel number, the process of joining the first and second binary images by the random joining processing means is performed for all the pixel rows in the joining direction in all the joining directions. And a control unit for connecting the first and second binary images as a whole to the pixel column.

According to a third aspect of the present invention, the overlapping portions of the first and second binary images are combined with the digital first and second binary images having the adjacent arrangement relationship and having the overlapping portions. A storage medium storing a program for causing a computer to execute an image stitching process that stitches the first binary image and the second binary image, and the storage medium includes at least a part of the overlapping portion. As a result of applying a first mixture ratio that reduces the weight of the pixel on the second binary image side to the density data of each pixel in the pixel row in the connecting direction of the first binary image belonging to the region And for the density data of each pixel belonging to the composite area in the pixel row in the joining direction of the second binary image corresponding to the pixel row in the joining direction of the first binary image, the first 2 Operates the second mixture ratio that reduces the pixel weight on the value image side A first step of performing a process of adding the combined result for each corresponding pixel and combining the pixels for each pixel column in the connecting direction, and a process of combining in the combining direction belonging to the combining area combined in the first step. A second step of performing a smoothing process on the density data of each pixel in the pixel array;
The third step of performing thresholding on the density data of each pixel in each pixel row in the connecting direction belonging to the composite area, which has been subjected to the smoothing processing in step 3, and binarizing the density data; The process including the fourth step of joining the first binary image and the second binary image including the result of binarizing in the step of step 4 is set as the joining step and is set in the overlapping portion. A joint position is randomly set for each pixel column in the joint direction, and a process of simply combining the first binary image and the second binary image with the joint position as a boundary is a random joint process. Density data of each pixel belonging to the overlapping portion in at least one pixel row in the connecting direction of the first binary image, and second density data corresponding to each pixel row in the connecting direction of the first binary image. At least 1 in the connecting direction of the value images
By comparing the density data of each pixel belonging to the overlapping portion in one pixel row, the density data of the pixel on the first binary image side and the density data of the pixel on the second binary image side are different. The number of pixels (deviation pixel number) is checked, and if the deviation pixel number exceeds a predetermined determination pixel number, each pixel row in the joining direction is subjected to the first and second fitting processes. Two
The value images are stitched together. On the other hand, if the number of shifted pixels is not more than the judgment pixel number, the first and second binary images are stitched together by the random stitching process for each pixel row in the stitching direction. A program that causes a computer to execute image stitching processing that performs stitching on all pixel rows in the stitching direction and stitches the entire first and second binary images is recorded in a storage medium. is there.

[0048]

According to the image stitching processing method of the first aspect of the present invention, the density data of each pixel belonging to the overlapping portion in at least one pixel row in the stitching direction of the first binary image and its density The density data of each pixel belonging to the overlapping portion in at least one pixel column in the joint direction of the second binary image corresponding to each pixel column in the joint direction of one binary image is compared with The density data of the pixel on the binary image side and the second 2
The number of pixels (deviation pixel number) different from the density data of the value image side pixel is checked, and if the deviation pixel number exceeds a predetermined determination pixel number, for each pixel row in the joining direction, The first and second binary images are stitched together in the stitching stitching process. On the other hand, if the number of misaligned pixels is less than or equal to the determination pixel number, random stitching process is performed for each pixel row in the stitching direction. The process of joining the first and second binary images is performed on all the pixel columns in the joining direction to join the entire first and second binary images.

That is, when the number of displaced pixels is relatively large, such as when the images in the overlapped portions of the first and second binary images have a large amount of displacement, for each pixel row in the joining direction. By joining the first and second binary images by the blending and joining process, the result of joining the images with high accuracy can be obtained as described above.

In the random joining process, the joining position set in the overlapping portion is randomly set for each pixel column in the joining direction, and the first joining position is defined as the boundary.
Since this is a process of simply synthesizing the binary image and the second binary image, for example, even when the image of the overlapping portion of the first and second binary images is the halftone image, Since the density data of pixels does not include multi-value processing such as blending processing of smoothing and joining processing or smoothing processing, there is no inconvenience that a halftone dot portion is blurred and disappears.

Therefore, as in the case where the overlapping portion of the first and second binary images is a halftone dot image and the halftone dot portion is deviated between the first and second binary images, the number of misaligned pixels is increased. When the number of pixels is relatively small, a relatively good image joining result is obtained by joining the first and second binary images by random joining processing for each pixel row in the joining direction. .

An image stitching processing apparatus according to a second aspect of the present invention is an apparatus that suitably implements the image stitching processing method of the first aspect, and its operation is as follows.

That is, the control means controls the density data of each pixel belonging to the overlapping portion in at least one pixel row in the connecting direction of the first binary image and each pixel in the connecting direction of the first binary image. The density data of the pixels on the first binary image side are compared with the density data of each pixel belonging to the overlapping portion in at least one pixel row in the joining direction of the second binary image corresponding to the row. The number of pixels (deviation pixel number) different from the density data of the pixel on the binary image side of 2 is checked, and if the deviation pixel number exceeds a predetermined determination pixel number, it is determined in each pixel row in the joining direction. On the other hand, the first and second binary images are stitched together by the stitching stitching processing means. On the other hand, if the shift pixel number is equal to or smaller than the determination pixel number, random for each pixel row in the stitching direction. Connects the first and second binary images with the joint processing means. The technique combining process, performed for all the pixel rows of the connecting direction, a first, joining the entire second binary image.

Incidentally, the synthesizing means constituting the smoothing joint processing means performs the first step of the smoothing joint processing of the invention described in claim 1, and the smoothing processing means performs the smoothing treatment of the invention described in claim 1. The second step of the joint processing is performed, the threshold processing means performs the third step of the familiarization joint processing of the invention described in claim 1, and the image joint means is performed of the invention described in claim 1. The fourth step of the familiarizing and connecting processing is performed to realize the familiarizing and connecting processing of the invention according to claim 1.

The random connection processing means is claimed in claim 1.
The random connection process of the invention described in 1. is realized.

According to the third aspect of the present invention, by causing the computer to read the program recorded in the storage medium, the computer executes the image connecting process according to the method invention of the first aspect.

[0057]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 10 is a functional block diagram showing the configuration of the image stitching processing apparatus according to the embodiment of the present invention.

The image splicing processing apparatus 1 shown in FIG. 10 includes an original image storage device 11, a discrimination unit 12, a blending splicing processing unit 13, a random splicing processing unit 14, and an image editing unit 1.
5, a post-processing image storage device 16, a setting instruction device 17, and the like. Further, the blending and joining processing means 13 includes a synthesizing means 13a, a smoothing processing means 13b, a threshold value processing means 13c, and an image joining means 13d similar to those in FIG.

In the original image storage device 11, for example, digital first and first digital signals of an adjacent arrangement relationship, which are provided from an input device 2 such as an appropriate scanner and have an overlapping portion WA in which the original OG is divided and read. 2 binary images NGA, NGB
Is stored in one or a plurality of sets. For the first and second binary images NGA and NGB to be joined, which are stored in the original image storage device 11, the discrimination unit 12
As will be described later, the first and second binary images NGA and NGB are joined together by the blending joining processing means 13, or the first and second binary images NG are joined by the random joining processing means 14.
It is determined whether to connect A and NGB. Then, the pixel row portion in the joint direction joined by the joint processing means 13 and the pixel row portion in the joint direction joined by the random joint processing means 14 are edited by the image editing unit 15.
The image NG after being joined to the image is edited and stored in the processed image storage device 16.

When the original image storage device 11 stores a plurality of sets of the first and second binary images NGA and NGB to be connected, the first and first binary images instructed by the setting instruction device 17. The two binary images NGA and NGB are joined together.

Also, a set of first and second binary images NG
For A and NGB, the density data of each pixel belonging to the overlapping portion WA in all the pixel rows in the connecting direction of the first binary image NGA and all the pixels in the connecting direction of the second binary image NGB. The density data of each pixel belonging to the overlapping portion WA in the column is collectively compared, and if the number of misaligned pixels exceeds the number of determination pixels, the entire first and second binary images NGA and NGB are equalized. If the number of misaligned pixels is equal to or smaller than the number of determination pixels, the first and second two are connected.
Random connection processing means 1 for the entire value images NGA and NGB
In the case of stitching at 4, the stitching processing means 13 or the random stitching processing means 14 edits the image NG after stitching. In that case, the image editing unit 15 smooths the stitches. The joint processing means 13 and the random joint processing means 14 are used in common.

The discriminating unit 12 and the image editing unit 15 constitute the control means in the invention described in claim 2.

FIG. 11 is a block diagram showing a concrete hardware configuration of the image stitching processing apparatus shown in FIG.

In the configuration of FIG. 11, the CPU 21 for executing various programs and the memory 2 for storing various data.
2, a storage device 23 such as a hard disk, a driver 25 that reads and writes digital data from and to a storage medium 24 such as a floppy disk or a CD-ROM, and a setting instruction such as a keyboard or a mouse that gives various setting instructions to the operator. The device 17 and the like are provided, and if necessary, a communication device 27 such as a modem that transmits and receives data via the communication medium 26, a display device 28, and the like are also provided. In addition,
Reference numeral 29 in FIG. 2 indicates a bus, and 30 indicates an input / output interface.

The image stitching processing program installed from the storage medium 24 storing the image stitching processing program and stored in the storage device 23 is read out to the memory 22, or the storage medium 24 storing the image stitching processing program is read. The image joining processing program is loaded into the driver 25 and the image joining processing program is read from the storage medium 24 into the memory 22, and the CPU 21 executes the program, whereby the determination unit 12 and the blending joining processing unit 13 are executed.
(Combining means 13a, smoothing processing means 13b, threshold value processing means 13c, image joining means 13d), random joining processing means 14, and image joining processing by the image editing section 15 are executed.

The CPU 21 includes the familiar joint processing means (combining means, smoothing processing means, threshold processing means, image joining means), random joint processing means, and control means in the invention described in claim 2. Constitute.

The storage medium 24 storing the image stitching processing program corresponds to the storage medium storing the program in the third aspect of the invention.

For example, the input device 2 is provided from the input device 2 in a state where the input device 2 is directly connected to the present device 1, or the communication medium 2 is used.
6 or the input device 2 via the communication device 27, or the first and second binary images NG to be joined.
A and NGB are stored in the storage device 23 and the storage medium 24. Further, the first and second binary images NGA and NGB are stored in the storage medium 24 by the input device 2, and the storage medium 2 is stored.
4 is loaded into the driver 25 and the first and second binary images N
GA and NGB may be given to the device 1.

The CPU 21 stores the first and second binary images NG to be connected (instructed by the setting instruction device 17) stored in the storage device 23 or the storage medium 24.
A and NGB are read into the memory 22, and the first and second
The binary images NGA and NGB are joined together as will be described later, and the joined image NG is stored in the storage device 23 or the storage medium 24 from the memory 22.

That is, the memory 22 and the storage device 2
3. The storage medium 24 corresponds to the original image storage device 11 and the processed image storage device 16 of the device configuration of FIG.

The stitched image NG stored in the storage device 23 or the storage medium 24 is used when the CPU 21 executes various image processing programs, or given to another device to be used in that device. It is used for image processing that is performed.

The CPU mounted on the input device 2 is
The first and second binary images NGA and NGB that have been read may be configured to perform the image stitching process according to the present invention. In that case, the input device 2 is the invention according to claim 2. The CPU which is also used as the image connection processing device according to the present invention and which is mounted on the input device 2 has the familiarization connection processing means (combining means, smoothing processing means, threshold value processing means, image processing) according to the invention of claim 2. A storage medium that stores an image connection processing program that is configured by a CPU mounted on the input device 2 and that stores the program according to the present invention. Corresponds to the medium.

Next, the image stitching method of the present invention will be described with reference to the functional block diagram shown in FIG. 10 and the explanatory diagram shown in FIG.

The discriminator 12 determines at least one pixel column GLAi to GLA in the connecting direction of the first binary image NGA.
[I + (s-1)] (i = 1, (1 + s), (1 + 2x)
s), ..., ( _YMAX- s), s = 1, 2, ..., _YMAX )
Pixels G (jHA, i to i +) belonging to the overlapping part WA in
(S-1)) (jHA = XWA, (XWA + 1), ...
(XWA + (WW-1)), where XWA is the overlapping part W
Density data (determined by A) (2 of "0" and "1")
Value density data) and at least one of the first binary images in the connecting direction of the second binary image NGB corresponding to each pixel row GLAi to GLA [i + (s-1)] in the connecting direction. Each pixel G (jHB, i ~ i + (s) belonging to the overlapping portion WA in the pixel columns GLBi to GLB [i + (s-1)].
-1)) (jHB = 1, 2, ... WW) density data (binary density data of “0” and “1”) is compared,
The pixel G (jHA, i to i +) on the first binary image NGA side
The number of pixels (deviation pixel number UG) in which the density data of (s-1)) and the density data of the pixel G (jHB, i to i + (s-1)) on the second binary image NGB side are different If the deviation pixel number UG exceeds the predetermined determination pixel number SG (UG> SG), each pixel row GLAi ...
GLA [i + (s-1)], GLBi to GLB [i +
(S-1)] is made to adapt to the connection processing means 13
The first and second binary images NG in the (blending process)
A and NGB are joined together, and on the other hand, the number of misaligned pixels UG
Is less than or equal to the determination pixel number SG (UG ≦ SG), each pixel row GLAi to GLA [i + (s−
1)], GLBi to GLB [i + (s-1)] are random joint processing means 14 (random joint processing).
To connect the first and second binary images NGA and NGB to all pixel columns GLA1 to GLA in the connecting direction.
Y _MAX , GLB1 to GLBY _MAX .

Further, the more the number of edge boundaries is, the larger the number of displaced pixels (UG) is, even if the position is the same. For this reason, the number of edges of the overlapping portion WA (referred to as EA) is counted and “UG
/ EA "may be obtained to make the determination.

Then, the image editing unit 15 edits the pixel row portion in the joining direction joined by the fitting joint processing means 13 and the pixel row portion in the joining direction joined by the random joining processing means 14, and the first , The second binary images NGA and NGB are joined together to obtain the joined image NG.

The switching of the connecting process may be performed for each one pixel column GLAi, GLBi (s = 1) in the connecting direction or several pixel columns GLAi to GLA [i + (s-
1)], GLBi to GLB [i + (s-1)] (where s in this case is 2 or more). In addition, all pixel columns GLA1 to GLA in the connecting direction
Y _MAX and GLB1 to GLBY _MAX may be collectively performed. How many pixel columns in the connecting direction the switching of the connecting process is performed may be determined depending on the image content of the overlapping portion WA of the first and second binary images and the degree of image deviation.

For example, one pixel column GLAi in the connecting direction,
When the connection process is switched for each GLBi, in the example of FIG. 13, the shift pixel is a pixel surrounded by a dashed line. The shift pixel number UG is “2” in the case of FIG. 13A (the same example as in FIG. 6) and is “2” in the case of FIG. 13B (when the image of the overlapping portion WA is a halftone image). 1 ".

Also, several pixel columns GLAi to G in the connecting direction
LA [i + (s-1)], GLBi to GLB [i + (s
−1)] (in the figure, s = 2), when the connection process is switched every time, in the example of FIG. 14, the shift pixel is a pixel surrounded by the alternate long and short dash line, and the shift pixel number UG is
In the case of (a) (corresponding to ΔGA and ΔGB in FIG. 18), it is “4”, and in the case of FIG. 14B (when the image of the overlapping part WA is a halftone image), it is “2”. .

The predetermined judgment pixel number SG for judging the switching of the connecting process is determined in accordance with the content of the image in the overlapping portion WA and the number of pixel columns in the connecting direction in which the switching of the connecting process is performed. In particular, it is set within a range in which the result of combining images by the random combining process is visually inconspicuous. For example, one pixel column GLAi in the connecting direction,
When switching the above-mentioned joining processing for each GLBi, if GS is set to "1", the pixel rows in the joining direction of FIG. 13A are joined by the fitting and joining processing, and then, FIG. The pixel rows in the joining direction of are joined by the random joining process.

The processing procedure is as follows: the number of shift pixels UG and the number of determination pixels S for each pixel row in the connection direction to be processed.
As a result of the judgment with G, the joint processing by the joint joint processing or the random joint processing for the pixel rows in the joint direction of the processing object, and the binary image after the joint may be edited in sequence, or in the joint direction. For each pixel row in the joint direction, the joint processing for merging each pixel row of is determined first for all the pixel rows in the joint direction, and for each pixel row in the joint direction for the joint processing. Perform joint stitching jointly and jointly perform joint jointing processing, and perform random jointing processing.Each pixel row in the jointing direction is jointly jointed and jointed by random jointing processing, and edit the result to obtain a binary image after jointing. May be.

As described above, according to the blending process, the number of shifted pixels UG is increased as in the case where the image of the overlapping portion WA of the first and second binary images NGA and NGB is greatly deviated. Even when there are relatively many, it is possible to obtain accurate image stitching results.

In the random connecting process, as shown in FIG. 17, the connecting position KL to be set in the overlapping portion WA is set randomly for each pixel row GLA, GLB in the connecting direction (random number is generated and set arbitrarily). Then, since the first binary image NGA and the second binary image NGB are simply combined with the joint position KL as a boundary, for example, the first and second binary images NGA are used. , NGB overlap W
Even when the image A is a halftone dot image, there is no inconvenience that the halftone dot portion is blurred and disappears without including the processing of converting the density data of pixels in the halftone dot portion into multi-valued data by the combining process and the smoothing process. Don't get up

Therefore, the first and second binary images NGA, N
When the overlapping portion WA of GB is a halftone dot image and the halftone dot portion is deviated between the first and second binary images NGA and NGB, when the deviation pixel number UG is relatively small, A relatively good image joining result can be obtained by joining the first and second binary images NGA and NGB by a random joining process for each pixel row in the joining direction.

[0085]

As is apparent from the above description, according to the image stitching processing method of the first aspect of the present invention, the overlapping portion in at least one pixel row in the stitching direction of the first binary image. Of the density data of each pixel belonging to the first binary image and each pixel belonging to the overlapping portion in at least one pixel row in the joining direction of the second binary image corresponding to each pixel row in the joining direction of the first binary image. Since the density data is compared and the blending joint processing and the random joint processing are selectively switched according to the number of misaligned pixels, the first and second binary images are joined together. It is possible to accurately join the images.

Further, since the joining process is switched for each at least one pixel column in the joining direction, the image contents and the degree of deviation of the overlapping portion of the first and second binary images are partially changed. Even when there is a change, it is possible to join the images by switching the joining processing according to the contents and the degree of deviation of the images of the respective portions within the overlapping portion, and it is possible to join the images of the pair of first and second binary images. It is possible to join the images as a whole with high accuracy.

According to the second aspect of the invention, it is possible to realize an image stitching processing apparatus which preferably implements the image stitching processing method of the first aspect.

According to the third aspect of the invention, it is possible to cause a computer to execute the image joining process according to the method invention of the first aspect.

[Brief description of drawings]

FIG. 1 is a functional block diagram showing a configuration of a familiarizing connection processing device.

FIG. 2 is a process conceptual diagram for explaining a familiarizing and connecting process.

FIG. 3 is a process conceptual diagram for explaining a first step of the familiarizing and connecting process.

FIG. 4 is a diagram showing first and second mixing ratios.

FIG. 5 is a diagram for explaining smoothing processing.

FIG. 6 is a diagram illustrating a processing example of a familiarizing and connecting process.

FIG. 7 is a diagram similarly showing a processing example by the familiarizing and connecting processing.

FIG. 8 is a diagram illustrating a first and a second image with a large image shift in an overlapping portion.
It is a figure which shows the process result which stitched together the value images by the process of fitting.

FIG. 9 is a diagram showing a distorted state of an image by an optical system in the input device when reading first and second binary images.

FIG. 10 is a functional block diagram showing a configuration of an image stitching processing device according to an embodiment of the present invention.

11 is a block diagram showing a specific hardware configuration of the image stitching processing device shown in FIG.

FIG. 12 is a diagram for explaining an image stitching processing method according to the present invention.

FIG. 13 is a diagram showing the number of misaligned pixels when the connection process is switched for each pixel column in the connection direction.

FIG. 14 is a diagram showing the number of misaligned pixels when the connection process is switched for every two pixel columns in the connection direction.

FIG. 15 is a diagram showing a relationship between an original document and a binary image obtained by joining first and second binary images.

[Fig. 16] Fig. 16 is a diagram for describing an image joining process in which a joining position is fixed and simple synthesis is performed.

FIG. 17 is a diagram for explaining a random joining process in which a joining position is randomly set for each pixel column in the joining direction and simple combining is performed.

[Fig. 18] Fig. 18 is a diagram illustrating an example of first and second binary images in which an image in an overlapping portion has a large deviation.

FIG. 19 is a diagram showing a result of joining the first and second binary images shown in FIG. 18 by a random joining process.

FIG. 20 shows the first and second binary images shown in FIG.
FIG. 6 is a diagram showing a result of joining by the image joining processing shown in FIG.

[Explanation of symbols]

1: Image stitching processing device 12: Discrimination unit 13: Familiar connection processing means 13a: Synthetic means 13b: smoothing processing means 13c: threshold processing means 13d: Image joining means 14: Random connection processing means 15: Image editor 21: CPU 22: Memory 24: Storage medium NGA: first binary image NGB: second binary image WA: Overlapping part of the first and second binary images

─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP-A-6-141228 (JP, A) JP-A-10-13769 (JP, A) JP-A-9-330396 (JP, A) JP-A-9- 23330 (JP, A) JP 10-178564 (JP, A) JP 11-17924 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) H04N 1/38-1 / 393 G06T 3/00

Claims (3)

(57) [Claims] 1. The first and second binary images are synthesized by combining the first and second digital binary images having an arrangement relationship and having adjacent layouts with each other. Value image and second
An image joining process for joining the binary image of the first binary image belonging to a composite area including at least a part of the overlapping portion with respect to the density data of each pixel in the pixel row in the joining direction. As a result of applying a first mixture ratio that reduces the weight of the pixel on the side of the second binary image,
The weight of the pixel on the side of the first binary image with respect to the density data of each pixel belonging to the composite area in the pixel row in the connecting direction of the second binary image corresponding to the pixel row in the connecting direction of the value image In the first step of performing the process of adding and synthesizing the result of applying the second mixture ratio for which the The second step of performing the smoothing process on the density data of each pixel in each pixel row in the connecting direction that belongs to the above-described combining region, and the combining region that has been subjected to the smoothing process in the second step. A third step of binarizing the density data of each pixel in each pixel row in the connecting direction by binarization, and the first step including the binarization result of the third step Two
A process including a fourth step of joining the value image and the second binary image is a joining process, and a joining position set in the overlapping portion is randomly set for each pixel row in the joining direction. Then, the process of simply synthesizing the first binary image and the second binary image with the joining position as the boundary is defined as random joining process, and at least one pixel row in the joining direction of the first binary image is formed. Of the density data of each pixel belonging to the overlapping portion of the first and second binary images corresponding to each pixel row in the joining direction of the first binary image.
Density data of pixels on the side of the first binary image and the second binary image by comparing the density data of each pixel belonging to the overlapping portion in at least one pixel row of the binary image of The number of pixels (deviation pixel number) different from the density data of the pixel on the side is checked, and if the deviation pixel number exceeds a predetermined determination pixel number, the same as above for each pixel row in the joining direction. When the first and second binary images are stitched together by the joint stitching process, and if the number of shifted pixels is equal to or smaller than the determination pixel count, the random stitching process is performed by the random stitching process for each pixel row in the stitching direction. An image stitching process characterized by performing the stitching process of the first and second binary images on all pixel columns in the stitching direction to stitch the entire first and second binary images. Method. 2. The first and second binary images, which are adjacent to each other and have a digital arrangement and which have an overlapping portion, are combined to form the first and second binary images. Value image and second
An image joining processing device for joining the binary image of the first binary image belonging to a composite area including at least a part of the overlapping portion to the density data of each pixel in the pixel row in the joining direction. As a result of applying a first mixture ratio that reduces the weight of the pixel on the side of the second binary image,
The weight of the pixel on the side of the first binary image with respect to the density data of each pixel belonging to the composite area in the pixel row in the connecting direction of the second binary image corresponding to the pixel row in the connecting direction of the value image Is added to each corresponding pixel and the result of applying the second mixture ratio for which the value becomes smaller is combined for each pixel column in the connecting direction, and the combined area combined by the combining unit. Smoothing processing means for performing a smoothing process on the density data of each pixel in each pixel row in the connecting direction belonging to, and each of the connecting directions belonging to the composite area subjected to the smoothing processing by the smoothing processing means. A first binary value including threshold value processing means for performing threshold value processing on the density data of each pixel in the pixel array to perform binarization, and a result of binarization by the threshold value processing means. Image stitching that stitches an image and a second binary image Fold-in joint processing means including a binding means, and a joint position to be set in the overlapping portion is randomly set for each pixel column in the joint direction, and the joint position is defined as a boundary, and a first binary image And a second binary image, a random joint processing means for simply synthesizing the second binary image, density data of each pixel belonging to the overlapping portion in at least one pixel row in the joint direction of the first binary image, and the first Of the second binary image corresponding to each pixel row in the joining direction
Density data of pixels on the side of the first binary image and the second binary image by comparing the density data of each pixel belonging to the overlapping portion in at least one pixel row of the binary image of The number of pixels (deviation pixel number) different from the density data of the side pixel is checked, and if the deviation pixel number exceeds the predetermined determination pixel number, it is not made to fit in each pixel row in the joining direction. The first and second binary images are stitched together by the stitching processing means. On the other hand, if the number of shifted pixels is less than or equal to the determination pixel number, the random stitching processing means performs the first stitching on each pixel row in the stitching direction. A control unit that performs the process of joining the first and second binary images to all the pixel columns in the joining direction to join the first and second binary images as a whole. An image stitching device characterized by: 3. The first and second binary images are synthesized by synthesizing the overlapping parts of the first and second digital binary images having an arrangement relationship adjacent to each other and having an overlapping portion. Value image and second
A storage medium storing a program for causing a computer to execute an image stitching process for stitching a binary image of the first binary image belonging to a synthesis area including at least a part of the overlapping portion. The result of applying a first mixture ratio that reduces the weight of the pixel on the second binary image side to the density data of each pixel in the pixel row of
The weight of the pixel on the side of the first binary image with respect to the density data of each pixel belonging to the composite area in the pixel row in the connecting direction of the second binary image corresponding to the pixel row in the connecting direction of the value image In the first step of performing the process of adding and synthesizing the result of applying the second mixture ratio for which the The second step of performing the smoothing process on the density data of each pixel in each pixel row in the connecting direction that belongs to the above-described combining region, and the combining region that has been subjected to the smoothing process in the second step. A third step of binarizing the density data of each pixel in each pixel row in the connecting direction by binarization, and the first step including the binarization result of the third step Two
The process including the fourth step of joining the value image and the second binary image is a joining process, and the joining position set in the overlapping portion is randomly set for each pixel row in the joining direction. Then, the process of simply synthesizing the first binary image and the second binary image with the joining position as the boundary is defined as random joining process, and at least one pixel row in the joining direction of the first binary image is formed. Of the density data of each pixel belonging to the overlapping portion of the first and second binary images corresponding to each pixel row in the joining direction of the first binary image.
Density data of pixels on the side of the first binary image and the second binary image by comparing the density data of each pixel belonging to the overlapping portion in at least one pixel row of the binary image of The number of pixels (deviation pixel number) different from the density data of the pixel on the side is checked, and if the deviation pixel number exceeds a predetermined determination pixel number, the same as above for each pixel row in the joining direction. When the first and second binary images are stitched together by the joint stitching process, and if the number of shifted pixels is equal to or smaller than the determination pixel count, the random stitching process is performed by the random stitching process for each pixel row in the stitching direction. The computer performs the image stitching process for stitching the entire first and second binary images by performing the stitching process of the first and second binary images on all pixel columns in the stitching direction. Memory for recording programs for Body.